US 12,283,796 B2
Spark plug
Natsuki Kurimoto, Nagoya (JP); Naomichi Miyashita, Nagoya (JP); Naoki Sakade, Nagoya (JP); and Kanji Higuchi, Nagoya (JP)
Assigned to NITERRA CO., LTD., Nagoya (JP)
Filed by Niterra Co., Ltd., Nagoya (JP)
Filed on Jan. 9, 2024, as Appl. No. 18/407,738.
Claims priority of application No. 2023-007907 (JP), filed on Jan. 23, 2023.
Prior Publication US 2024/0250508 A1, Jul. 25, 2024
Int. Cl. H01T 13/34 (2006.01)
CPC H01T 13/34 (2013.01) 8 Claims
OG exemplary drawing
 
1. A spark plug comprising:
a center electrode extending along an axial line;
a metal shell holding the center electrode with an insulator interposed therebetween; and
a ground electrode connected to the metal shell by a connection portion,
wherein the center electrode includes a protrusion, a discharge member, and a fused portion, the protrusion protruding from an end of the insulator, and the discharge member being joined to the protrusion and forming a spark gap between the ground electrode and the discharge member, the fused portion joining the discharge member to the protrusion, and
wherein a recess is formed at a position including the protrusion.